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John McCain and Barack Obama will face off in their third and final debate at Hofstra in a few hours. But as bad as McCain's prospects were at the start of the day, they're now getting worse by the minute. Today's plunge in the Dow—it's been down several hundred points for most of the afternoon—has led to a new low for him on InTrade, which now estimates his chances of winning the election at 1-in-5. [Clusterstock]